Patent EA-012013-B1 (EA)
Title: Bimetallic ridged brake shoe for locomotives and railmotor cars
Inventor: TEMNIKOV FEDOR SERAFIMOVICH
IPC: B32B1/06
Filed: 2008-08-19
Abstract: The invention relates to railway transport, in particular, to brake equipment of traction rolling stock and also can be used in other transport means using braking systems. A bimetallic ridged brake shoe for locomotives and railmotor cars comprises a black iron arc-like body made up of the main and section parts with a passage made therein, the body has friction elements embodied as cylindrical inserts. The inserts of the main section of the brake shoe are placed in the brake shoe body on the friction surface side where arranged by two groups separated by section without inserts P. The main section inserts are placed in the passage. Inserts are made of material whose abrasiveness is higher than material of the brake shoe body, the inserts are welded the steel plate. The brake shoe body main section has a transversal boss on the rear side with a hole for a wedge key. The shoe is iron cast in a mould. The main section of the arc-like body is provided on the side setting thrust T-shaped projections for conjugation with the brake shoe and rigidity ribs as triangular bosses connecting the main and section parts. The section part passage has depth exceeding the wheel tread top by 0.85 of the shoe main section thickness. The steel plate is embodied as a one piece element or a composite element consisting of two or three welded parts. The steel plate covering the main section of the shoe body embraces a transverse cast iron boss and has holes in side surface at holes level in the boss for the wedge key. Mounting holes are made in the steel plate for fixing inserts. Five metal inserts are mounted from the side of friction surface perpendicular to the outer side wall of the section part passage. The composite metal plate may comprise two parts, one part embraces the arc-like rear surface of the main part of the shoe having the transverse boss and moves to the shoe section part closing its upper part, the other part embraces the outer side wall of the section part. The composite metal plate may comprise three parts, one part embraces the arc-like rear surface of the main part of the shoe having the transverse boss, a second part embraces the inner side wall of the section part closing its upper part, a third part embraces the outer side wall of the section part. The insert centers of the section part are serially arranged along the ridge arc base of the wheel tread or alternately displaced by 20 mm up and down relative to the ridge arc base of the wheel tread, the insert centers are equally spaced from each other along the ridge arc base of the wheel tread, and the extreme inserts are removed from the shoe ends at 0.5 distance between inserts. Inserts are made of steel or metals and their alloys, 16-24 inserts are embedded in the shoe main part body. The area of the section P (without inserts) between insert groups is determined by the formula: P=(0.17-0.19)R, where P is section area without inserts; R is whole area of the working brake shoe. The diameter of the section part inserts equals to the diameter of the main part inserts and makes up: D=L: (0.13-0.17), where Lis a shoe length, mm; D is insert diameter, mm; Insert length Lof the shoe main part makes up: L=(0.84-0.86)xH, where His shoe thickness, mm; Insert length Lof the shoe section part makes up: L=(0.7-0.72)xH, where His thickness of the section part side wall. The inserts are welded to the steel plate from rear side through the mounting holes in pairs using an automatic welder. The proposed brake shoe embodiment permits to improve operation reliability and effectiveness thereof due to higher strength and better production technology thereof. The embodiment excludes arising transversal thermodynamic cracks on top of wheel tread ridge and their subsequent development in the wheel tread body thus increasing life time of rolling stock wheels.